The principal aims of this research program are (a) the development of novel spectrofluorimetric and other spectroscopic methods for the elucidation of the structure and dynamics of macromolecular assemblies, (b) the application of these techniques to obtain insight into selected excitable membrane systems. During 1976, we will focus on (a) fluorescence energy transfer and fluorescence correlation studies of gramicidin A, a transport antibiotic, to determine the dynamics of channel formation, (b) C13-NMR studies of C13-labeled formly gramicidin, to determine the location of gramicidin in lipid bilayer membranes and elucidate the conformation of the transmembrane channel, (c) the design and synthesis of voltage-sensitive probes, which will be evaluated using our electric field apparatus, and (d) the construction of a time-resolved Raman spectrometer, which will be used to obtain resonance Raman spectra of transient species such as the intermediates in visual excitation. Bibliographic references: Renthal, R., Pober, J.S., Steinemann, A., and Stryer, L., Concanavalin A-Agarose in the Study of Rhodopsin and Its Derivatives, in Concanavalin A as a Tool, ed. by H. Bittiger and H.P. Schnebli, J. Wiley and Sons, Ltd. 1975.